Manufacture of starch



0t-rl2u7 I -:f RE. GRENFIELD .2,053,683-

MANUFAGTURE oi' sTARcH original Fired sept. l2:5, 1952 Patented Oct, [275, 1.936;

ESS

Robert Edman Greenileld, Decatur to dit. Staley Manui'act lll., assignm- Company, Dcl catur, Ill., a corporation ol ilel'aware Application september es, iosa. soun no. states Renewed Setom it, i935 tortiera v This invention relates to the manufacture 'ot `starch'iroxn corn and has more particular reierence to improvement in the handling and use.

of the waters employed in enecting the separa-v 5 tion of the starch from the other ingredients, and

to the recovery of the solubles.

The manufacture of'starch from corn is aocomplished fundamentally by water separation and flotation operations and heretofore has conflil sisted generally in first soaking or sleeping the starch' from corn which, while returning the various waters for reuse in the process. will per- -mit ol separate and independent control of the `volunies ol water used in the mill house to sepa corn, then breaking up the kernels `so that the' corn germs may be removed from the starch bearing materials; thereafter grinding the starch bearing materials to separate the starch Aand- 'it 'gluten from the brany and fibrous lparts and d nally separating` the starch and the gluten. all ot these .operations are carried on with the use oi large quantities of Water employed to convey the corn duri its disintegration through the various grinding mills, screening reels, hlters, ete., and with the use also oi a large amount of Water to nei-mit a gravity separation oi the starch and gluten and the doating ou of theljgluten tor scirarate disposition. i

'.ihe corn contains a substantial percentaae'oi' rate the sions from the starch milk, and in the 5 table house to separate the starch from the uluten. Moreover, in the manufacture oi starch from corn it is desirable that separate control be'nossible in the mill house and at/the starch tables, drst oi the temperatures of the waters 1o and "second oi' their/ sulphur dioxide concentration.

e invention contemplates a closed water system lor the mill house and through the steeps, which is separate irom a closed water system it nrovlded tor the separation of the gluten irom t the starch. v

' another object ol the invention is the re-A movai oi all or substantially all of the solubles heiore tabling the starch in order that opporitil trinity ior fermentation at the tables may be nrevented or minimized and starch of improved ditty produced.

soluble material in addition to the insoluble'- germs, fibers, starch, and gluten. I t soluble components must, of course, be removed trom the starch and should be recovered trom the Waters dissolving. them since they are advantageously usable in the manufacture ol stock leed. After removal of the germs the remainder ol the corn kernels is ground in suitable tra?" and the grind is successively passed through `sieves or screens to separate the bran and hbrous materials from the starch and gluten, this bran and iibrous material being known generally in the industry as slops.

dit

ina. discloses a preferred embo lll'erous other objects and advantages oi the invention `will be apparentes it isbetter understood from the rollos/lng' description, which, when taken in connection with the accompanying drawdiment thereof.

'ci the solubles and is delivered out through a Ilhe separation of the slops from the starch,-

milk (water containing starch and gluten) is best and most economically accomplished when a dennite volume of water per bushel of corn ground is maintained. Likewise the separation of the gluten from the starch is best and most advantageously accomplished when a predeterf mined definite volume of Water per bushel oi corn ground is used in the separation.

Also in the manufacture oi starch from corn it is desirable that the water used in the several 5o operations be conserved and returned to the system' in order that the solubles may be concealI trated for recovery and water be needed. l,

The principal object ci this invention is the provision of a process for the manufacture ol dit " Filed mill) a\minimum amount oil line,v indicated at it, for evaporation in pans or otherwise." Alter washing, the corn from which most ol the steep Water hasbeen removed is de- @lo livered` by a line it for breaking up in an attrition mill it (identified on the now sheet as a in this millV the corn isbroken sufeiently to permit separation of most of the g." rn the mill it the corn passes'by a 45 lineid into a germ separator it wherein such eer-ms as have been liberated from the corn are floated od viur delivery to a germ washing system to be presently described. The remainder oirthe oorn'i'romthe separator is delivered by a ,50 line il, into a vseparator reel it vin which such starch'and gluten as have been separated are f removed.

The partially degerminated corn lis delivered lr-'the separator reel I8 by aline iii to aV second 55 attrition (Foos) mill 2| where the corn is further broken up to permit removal of the remaining germs. These germs with the residual fiber and starch constituents are delivered through a line 22 into a second germ separator 23 from which the remaining germs are floated ofi. v

From the separator 23 the starch bearing material is delivered by a line 24 to a second starch separator reel 25 for removal of existent free starch and gluten. From the reel 25 the remaining starch bearing materials are carried by a line 26 to a grinding mill 21 (identified on the ow sheet as a Buhr mill), Where they are finely broken up and delivered through a line 28 successively to two series of separators for removing, first, the coarser fibrous materials and bran (together called coarse slops) and then for removing the finer bran and bers (called fine slops).

-The series of separators are indicated respectively by reference characters 29 and 3|. In these two series of separators the corn bearing material isserially treated with attendant removal of starch and gluten.

As will be presently more fully explained, a counterflow of water is provided to. advance the starch nearing materials successively through the separating units. The starch milk from -which the germs and the slops have been separated is next delivered to a 4water extractor 32 in which the water, which has been carrying the starch and gluten, is extracted and the starch and gluten mixture washed and filtered.

'I'he starch which has been separated out at the lseparators I8 and 25 is conveyed by pipes 33 and 34 into a pipe 35 leading to a shaker separator 36. From this separator the starch milk is conveyed by a line 31 into the shaker separator 38, which is the separator at the head of the series of fine *slop separating system, and from this separator 36 the separated slops are carried by a line 39 into line 26 leading to the grinding mill 21.

All of the starch milks produced are therefore concentrated in the shaker 38 and from this shaker are delivered by a line 4I into the water extractor 32. By dewatering the starch milk in this manner the quantity of liquid water is reduced to the desired extent. As is understood in the art, the water extractor or thickener 32 may be a centrifugal separator, or a settling tank, but preferably is a lter, so that the washing and filtering of the starch and gluten may be effected easily.

The water of the starch milk is withdrawn from the water extractor 32 by a line 42 which is divided into three branches at 43. One of these branches 44 supplies water for the countercurrent flow of the fine slop system; another of these branches 45 supplies water through the countercurrent flow of the coarse slop system; and the third branch 46 supplies Water for countercurrent flow through the reels 41 of the germ washing system. As will be presently more fully described, additional wa'ter is supplied into the line 42, already described, from the nal starch washing apparatus.

From the head reel 48 of the germ washing system a line 49 supplies water through branches 5I and 52 into separators I6 and 23 and water also through branch 53 into line I3 arrangedbetween the steep house and the first a1-rition mill.

A certain amount of starch milk is supplied from -the separators I8 and 25 through a line 54 into line 49 to be delivered into the separators 'apparatus is to provide desired Baum for the flotation of the germs from the remainder of the corn.

A line 55 leads from the first reel of' the flne i slop series 3| to three branches 56, 51 and 58 for delivery of an amount of starch milk into the second attrition mill 2I and into the separators I6 and 23 respectively to supplement the starch milk delivery through line 49. The remainder of the water coming from the germ washing system is delivered through the line 59 into line 55.

A part of the overflow from the Water extractor is conveyed by line 6I leading from line 42 into the steeps for use in steeping the corn and flnal exit out to the evaporating pans. Other incidental lines or conduits are put in to convey the waters between the various units of the system as may be required and as indicated on the flow sheet, the foregoing being thought sufficient to describe generally the extraction of the water from the starch milk at the extractor'32.

In the operation of so much of the apparatus as has already been described, the major portion of theA solubles is carried by the overflow back into the system finally leaving it by line 6I through the steeps into evaporating pans through line I2. The remaining portion of the soluble ingredients may be and preferably is removed in the washing apparatus contained in the thickener or filter 32. Fresh water is introduced into this unit by a line 1I and the wash water removed from the filter through a. line 12 is delivered into line 42 as indicated upon the flow sheet. The washed and dried mixture of starch -and gluten ls next delivered into a repulping device, called a breaker on the flow sheet, indicated by reference character 13.

The repulping device Vis located in a closed water circulating system which comprises starch tables 14, on which the starch and gluten are separated, a gluten settler 15 and a gluten lter'l in which the gluten is separated from the water, and pipe lines, 4including a line 16 leading from the repulping apparatus to the tables 14, and a line 11 leading from the tables 14 into the gluten settler 15 and a line 18 leading from the gluten settler into the repulping apparatus. The water from the gluten filter joins line 9I and is carried back to line 18 along with make-up water from the starch washing system as will afterwards be referred to. The water is caused to flow through this circuit and the gluten settler water is thus used to deposit the starch upon the tables and to float Off the gluten into the gluten settlers.

The starch is ushed from the tables with fresh water and preferably by a loop system which delivers the water after use up into the mill house and to the steeps. This system comprises a line 19 delivering fresh water to a filter 8| and line 82 delivering the filtrate across the tables 14 for flushing, a line -83 leading from the tables to a shaker 84, and a line 85 leading through the filter 8 I, this last carrying the starch into the lter for filtration. The grits taken from-.the shaker 84 and apercentage of the water are delivered by a line 86 up for return into the flneslop system through line 31.

A line 81 conveys a part of the filtrate of the filter 8| to a check filter 88 and the filtrate from this iilter is carried by a line 89 up to lines 42 anun for denveryto the stfeps and te the min. house. 89 audit-in order -to supply make-up water into lrshe gluten starch separating system as may be .5 8

-slop systems just ahead of the Iiinal reels which deliver the coarse and line slops and are thereafter passedthrough the earlier acting separat-- ing reels of the system.

It will be manifest that the circulation of water around through the ilne and coarse slop systems the tables and baclithroug'h the filter.

and starch by the is wholly independent from the circulation of water over the tables and accordingly is subject to separate concentration controls and to separate controlof temperature and oi sulphur'dioxide v concentration. Each system y be adjusted in each of these regards as is most advantageous or calculated to produce best emciency of action and economy of operation.

Itis thought that the invention and many of its attendant advantages Will be understood from the foregoing description and it will be apparent that various changes may-be made in the steps and their order of accomplishment of the process described without departing from the spirit and scope of the invention or sacricing all of its material advantages, the process herein before described bodiment thereof.

I claim: g

l. The process oi' manufacturing starch from corn, which comprises removing the slops and a major portion of the solubles from the gluten and starch by the use of water, devvatering the gluten and starch, Washing the dewatered gluten and starch, introducing the starch and gluten into a closed continuous how oi Water passing over a table on which the starch separates from the water, and iiushing the starch from said table with Water, taking upany residual solubles and ltering, the removal of the starch from the table and the ltering being accomplished by a stream of Water entering the lter thence passing over 2. The process of manufacturing starch from corn, which comprises removing the slops and a major portion of the solubles irom the gluten use of. Water, vdervatering the gluten and starch,

introducing the starch and gluten into a closed i continuous iioW or water 'passing overa table on which the starch separates from the gluten and through a settler in which the gluten separates from the water, and ushing the starch from said table'with water taking up any residual so-lubles, and filtering, the removal of the starch from the table and' the nltering beingvaccompiished bya stream of waterentering the nlter thence passing over the tables and back through the filter, and thereafter using the last mentioned Water in the separation of the starch and gluten from theslops.

3. In the process of recovering starch and "other products from corn Vin which the corn is steeped, cracked, degerminated by starch milk notation, subjected to a washing process for removal of brousmaterials, tabled for separation of the A line 9| is provided between -tlie'lines` being merely a preferred em- .l

washing the gluten and starch,

starch from .the gluten," and the gluten is dewateredthe improvement which comprises com.

`mixture-'washingthe dewatered starch gluten mixture, steeping additional corn with the' water from'said mixture, and adding to the dewatered starch-gluten mixture the water which is separated from the gluten.

4. The process of recoveringstarch and other products from corn, which comprises-1 steep ing the dcorn in water. cracking the steeped corn, removing.: the germs from the cracked corn bystarch milk notation, grinding the degerxninated corn, separating the iibrous constituents of the corn from the starch-gluten mixture thereof by water washing, mixing the starch-gluten mixtures from the germ dotation with the starch-gluten mixture separated 'irorn said nbrous constituenta'dewatering said starchgluten mixtures, washing the dewatered starchgluten mixtures. steeping' additional cornv with the water from said starch-gluten ture adding Water to said starch-gluten mixtures, separating the starch .from said starch-gluten mixtures, separating the water irom said glutenand adding said separated water to the detered starch-gluten mixtures.

5; The process of recovering starch and other lproducts from corn, which comprises steeping the corn, cracking the steeped com,rrenioving the germs from the cracked corn by starch4 milk lnotation, grinding the corn, separating the dbrous 'constituents oi the corn from the starch-gluten mixture therein, dewatering and washing the starch-gluten mixture, washing said germs and said iibrous constituents with the Water obtained thereby, adding water to the dewatered starchgluten mixture, separating the starch from said mixture, Washing said starch, steeping additional corn with said starch wash water and with the water obtained from said devvatered starchgluten mixture, ,dewatering said gluten, and adding the Water from said gluten to the de watered starchegluten mixtur 6. 'line process of recovering starch and other products from corn, which comprises steeping the corn, cracking the steeped corn, separating the germs :from the cracked corn by starch milk dotation, grinding thecorn, separating the hbrous material from the ground corn by water wasg, dewateringand washing the starch-gluten mixture obtained by said operations, returning the water obtained thereby to said operations, adding i additional water to the dervatered starch-gluten mixture, separating the starch from the re= watered starch-gluten mixture, devvatering the gluten, employing the water obtained trom said gluten as said additional Water for the starchgluten mixture, Washing said starch, and passing a portion of the starch wash water into the proc- -ess ahead oi the dewatering step for the starchgluten mixture.

7.The process of recovering starch from corn, which comprises steeping the corn, cracking the steeped corn,` separating the germs from the nation by starchmi1k flotation. subjecting the y degerminated com to a washing operation to produce a starch-gluten suspension in water, dewatering the starch-mill: from the notation and the starch-gluten suspension, subjecting-the dewatered materials to a washing operation with fresh water, subjecting said materials to an operation ior removal oi starch therefrom and to produce a water suspension of gluten, dewaterins s,oss,cas

said water suspension ot gluten and adding the water therefrom to said washed materials.

9. The process of recovering starch and other .products from corn by the wet milling method.

which comprises steepingV the com. subjecting the steeped corn to a series o! washing operations ier-the production of a starch-gluten suspension in water, dewatering said suspension, washing the dewatered suspension with fresh water, subjecting the washed materials to a separating operation in water for removal ot starch therefrom .and for producing a water suspension 4of gluten,

dewatering the gluten, and returning the water from said gluten to said separating operation.

ROBERT mum ummm. 

